Experiments will be conducted on the effect of specific reagents for labeling the functional groups at the active sites of coupling factors F1 and CF1 respectively. Kinetic studies will be made on these labeling reactions in the presence or absence of ADP, ATP, inorganic phosphate and their analogues. It is also planned to study quantitatively the conformation changes in these coupling factors with the help of fluorescent labels bound covalently to the active sites. It seems likely that the data so obtained will give us useful information on the structure of these coupling factors. The control mechanism for regulating proton leakage through CF1 and F1 will also be investigated by fluorometric and potentiometric measurements. Since oxidative phosphorylation is the backbone of our metabolism, a fuller understanding of its molecular mechanism is potentially of great importantce to helth. We hope that the information obtained in this way will be useful in the eventual elucidation and control of this energy transducing process which regulates growth and sustains us in the living state.